This invention relates to the analysis of video signals and, more particularly, to a method and apparatus for reliably detecting motion of an object represented by a video signal.
In a number of diverse arts such as television, radar, and ultrasonic medical diagnosis, a video signal represents an image or object to be portrayed on a cathode ray tube or other display device. In a two-dimensional display, the video signal is composed of a plurality of adjacent lines that form repetitive frames representing the image or object at successive points in time. To increase the information that can be extracted from a video signal, the video signal can be processed in various ways. For example, the image appearing on the display can be enhanced.
For the purpose of medical diagnosis, it is frequently necessary to determine the movement of body organs such as heart rate and breathing characteristics. In the past, motion detection of body organs has been accomplished ultrasonically with an A-scan. But for many other viewing purposes, a B-scan or a sector scan is preferred to an A-scan in ultrasound diagnosis. Thus, separate ultrasound apparatus had to be employed to view images of body organs and to detect their motion.